ADE7756ARS Analog Devices Inc, ADE7756ARS Datasheet
ADE7756ARS
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ADE7756ARS Summary of contents
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GENERAL DESCRIPTION The ADE7756 is a high-accuracy electrical power measurement IC with a serial interface and a pulse output. The ADE7756 incorporates two second-order sigma-delta ADCs, reference circuitry, temperature sensor, and all the signal processing required to perform active ...
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ADE7756 FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 ...
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SPECIFICATIONS DD T MIN Parameter ENERGY MEASUREMENT ACCURACY Measurement Bandwidth 1 Measurement Error on Channel 1 Channel 1 Range = 1 V Full Scale Gain = 1 Gain = 2 Gain = 4 Gain = 8 Gain = ...
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ADE7756–SPECIFICATIONS Parameter REFERENCE INPUT REF Input Voltage Range IN/OUT Input Capacitance ON-CHIP REFERENCE Reference Error Load Current Output Impedance Temperature Coefficient CLKIN Input Clock Frequency LOGIC INPUTS RESET, DIN, SCLK, CLKIN and CS Input High Voltage, V INH Input Low ...
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TIMING CHARACTERISTICS Parameter A, B Versions Unit Write Timing (min 150 ns (min 150 ns (min (min (min) 5 µs (min) t 6.4 6 µs ...
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... ADE7756 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high-energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality. Model ADE7756AN ADE7756BN ADE7756ARS ADE7756ARSRL ADE7756BRS ADE7756BRSRL EVAL-ADE7756EB ADE7756AN-REF Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . 150°C 20-Lead Plastic DIP, Power Dissipation . . . . . . . . . 450 mW θ ...
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Pin No. Mnemonic Description RESET 1 Reset Pin for the ADE7756. A logic low on this pin will hold the ADCs and digital circuitry (including the Serial Interface reset condition Digital Power Supply. This pin provides ...
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ADE7756 Pin No. Mnemonic Description CS 17 Chip Select. Part of the 4-Wire SPI Serial Interface. This active low logic input allows the ADE7756 to share the serial bus with several other devices—see Serial Interface section. 18 SCLK Serial Clock ...
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C 0.30 0.20 0.10 + +25 C –0.10 –0. –0.30 GAIN = 1 ON-CHIP REFERENCE –0.40 –0.50 0.01 0.10 1.0 10.0 AMPS 0. GAIN = 2 0.40 ON-CHIP REFERENCE ...
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ADE7756 0. GAIN = 8 0.40 ON-CHIP REFERENCE 0.30 +85 C 0.20 0.10 – +25 C –0.10 –0.20 –0.30 –0.40 –0.50 0.01 0.10 1.0 AMPS 0. GAIN = 16 0.40 ON-CHIP REFERENCE ...
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V DD 40A 100nF TO 40mA 10 F RESET DOUT 1k V1P U1 SCLK 33nF RB ADE7756 1k V1N 33nF CLKOUT CLKIN V2N 33nF 1k 1M SAG V2P 33nF 1k 110V REF IN/OUT 100nF 10 ...
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ADE7756 ANALOG INPUTS The ADE7756 has two fully differential voltage input channels. The maximum differential input voltage for each input pair (V1P/V1N and V2P/V2N) is ± addition, the maximum signal level on each analog input (V1P, V1N, ...
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The contents of the Offset Correction registers are 6-bit, sign and magnitude coded. The weighting of the LSB size depends on the gain setting, i.e 16. Table II below shows the correctable offset span for ...
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ADE7756 LINE VOLTAGE SAG DETECTION In addition to the detection of the loss of the line voltage signal (zero crossing), the ADE7756 can also be programmed to detect when the absolute value of the line voltage drops below a certain ...
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INTERRUPTS Interrupts are managed through the Interrupt Status register (STATUS[7:0]) and the Interrupt Enable register (IRQEN[7:0]). When an interrupt event occurs in the ADE7756, the corre- sponding flag in the Status register is set to a Logic 1—see Interrupt Status ...
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ADE7756 TEMPERATURE MEASUREMENT ADE7756 also includes an on-chip temperature sensor. A tem- perature measurement can be made by setting Bit 5 in the Mode register. When Bit 5 is set logic high in the Mode register, the ADE7756 will initiate ...
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Antialias Filter Figure 21 also shows an analog low-pass filter (RC) on the input to the modulator. This filter is present to prevent aliasing. Alias- ing is an artifact of all sampled systems. Figure 16 illustrates the effect, frequency components ...
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ADE7756 CHANNEL 1 ADC Figure 18 shows the ADC and signal processing chain for Chan- nel 1. In waveform sampling mode the ADC outputs a signed two’s complement 20-bit data word at a maximum of 27.9 kSPS (CLKIN/128). The output ...
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SAMPLING RATE (27.9kSPS, 14kSPS, 7kSPS OR 3.5kSPS) IRQ 16 s SCLK READ FROM WAVEFORM DIN HEX DOUT SIGN CHANNEL 1 DATA – 20 BITS CHANNEL 2 ADC Channel 2 Sampling In Channel 2 waveform sampling mode ...
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ADE7756 PHASE COMPENSATION When the HPF is disabled, the phase error between Channel 1 and Channel 2 is zero from dc to 3.5 kHz. When HPF1 is enabled, Channel 1 has a phase response illustrated in Figures 23 and 24. ...
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ACTIVE POWER CALCULATION Electrical power is defined as the rate of energy flow from source to load given by the product of the voltage and current wave- forms. The resulting waveform is called the instantaneous power signal and ...
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ADE7756 ENERGY CALCULATION As stated earlier, power is defined as the rate of energy flow. This relationship can be expressed mathematically as Equation where P = Power, and E = Energy. Conversely, Energy is given ...
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POWER OFFSET CALIBRATION The ADE7756 also incorporates an Active Power Offset regis- ter (APOS[11:0]). This is a signed, two’s complement, 12-bit register that can be used to remove offsets in the active power calculation—see Figure 30. An offset may exist ...
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ADE7756 reduce the ripple. Also, averaging the output frequency by using a longer gate time for the counter will achieve the same results. E(t) VIt /8.9Hz ENERGY CALIBRATION By using ...
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Assuming the meter is set up with a test current (basic current and a line voltage of 220 V for calibration, the load is calculated as 220 V × 4.4 kW. Therefore the expected ...
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ADE7756 SUSPENDING THE ADE7756 FUNCTIONALITY The analog and the digital circuit can be suspended separately. The analog portion of the ADE7756 can be suspended by set- ting the ASUSPEND bit (Bit 4) of the Mode register to logic high—see Mode ...
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The data is always assumed to be right justified, therefore, in this case, the 4 MSBs of the first byte would be ignored and the 4 LSBs of the first ...
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ADE7756 No. of Address Name R/W Bits 00h Not Used 01h WAVEFORM R 24 02h AENERGY R 40 03h RSTENERGY R 40 04h STATUS R 8 05h RSTSTATUS R 8 06h MODE R/W 16 07h CFDIV R/W 12 08h CH1OS ...
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No. of Address Name R/W Bits 10H IRQEN R/W 8 11H SAGLVL R/W 8 12H TEMP R 8 REGISTER DESCRIPTIONS All ADE7756 functionality is accessed via the on-chip registers. Each register is accessed by first writing to the communications register ...
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ADE7756 Mode Register (06H) The ADE7756 functionality is configured by writing to the MODE register. Table VI summarizes the functionality of each bit in the MODE register. Bit Bit Location Mnemonic Description 0 DISHPF The HFP (High-Pass Filter) in Channel ...
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Interrupt Status Register (04H) / Reset Interrupt Status Register (05H) The Status register is used by the MCU to determine the source of an interrupt request (IRQ). When an interrupt event occurs in the ADE7756, the corresponding flag in the ...
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ADE7756 0.210 (5.33) 0.078 (1.98) 0.068 (1.73) 0.008 (0.203) 0.002 (0.050) OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 20-Lead Plastic DIP (N-20) 1.060 (26.90) 0.925 (23.50 0.280 (7.11) 0.240 (6.10 0.325 (8.25) PIN 1 0.300 ...